Chipper



y 1967 A. ZAICHKOWSKY 3,319,674

CHIPPER I Filed Dec. 9, 1964 2 Sheets-Sheet l FIGI INVENTOR. ANDREW ZAICHKOWSKY I I and, I E/4'0 A TTORNE Y6:

May 16, 1967 A.- ZAICHKOWSKY 3,319,674

CHIPPER Filed Dec. 9, 1964 2 Sheets-Sheet 2 INVENTOR.

ANDREW ZAICHKOWSKY United States Patent Ofiiice 3,319,674 Patented May 16, 1967 3,319,674 CHIPPER Andrew Zaichkowsky, Montreal, Quebec, Canada, as-

signor to Carthage Machine Company, Inc., Carthage, N.Y., a corporation of New York Filed Dec. 9, 1964, Ser. No. 417,931 Claims. (Cl. 144176) This invention relates to chippers and more specifically to an improved chipper for producing chips from wood slabs and the like.

Apparatus for converting Wood logs, slabs or the like into chips for various uses such as the production of paper, paperboard, hardboard, or similar products are well known to the art. These chippers generally comprise a large metal disc rotata'bly mounted on the shaft fixed to a supporting frame. Chipping knives or blades are circumferentially spaced around the disc, and extend outwardly from the face of the disc in the dirction of a fixed feed spout mounted on the chipper adjacent and parallel to the disc. The wood to be chipped is fed into and supported by the feed spout close to the disc so that the rotation of the disc brings the blades into chipping engagement with the wood.

In conventional horizontal feed chippers the feed spout is positioned below the center of rotation of the disc, and the chipping blades are generally secured to the disc in a radial direction. These prior art chippers have been characterized by certain disadvantages when used for chipping slabs or other similar flat wood members.

A major disadvantage of conventional chippers in chipping slabs and the like is that the chipping blades tend to tilt the slab in the feed spout. The thus tilted slabs tend to fall back to a horizontal position by gravity. However, the continuous rotation of the disc brings additional blades into contact with the slabs Causing them to vibrate within the feed spout. This vibration and instability of the slabs in the feed spout not only increases the wear on the chipper blades and other chipper parts but also results in a very poor quality, non-uniform chip. Further when the slabs become shortened near the end of the chipping operation, they tend to be rotated lengthwise to a position parallel with the disc. This rotation results in the formation of slivers.

It is therefore a primary object of this invention to provide an improved wood chipper for chipping slabs and the like in which vibration of the slabs during the chipping operation is minimized thereby producing high quality chips and reducing damage to the chipper assembly.

It is an additional object of this invention to provide an improved efiicient and stable slab chipper having a horizontal feed spout above the axis of rotation of the disc, nonradial chipping blades having their outer ends angularly displaced in the direction of rotation of the disc to exert a downward force on the slab during substantially the entire chipping operation.

Generally the invention relates to a chipper for chipping wood slabs and the like comprising a hood or housing, a vertical cutting disc rotatably mounted on a horizontal shaft in said housing, a feed spout extending into the housing to receive a slab to be chipped, said feed spout including a flat horizontal base to support the slab during the chipping operation, said base having its inner end adjacent the outer face of said disc, said inner end being above the center of rotation of said shaft and laterally displaced from said shaft in the direction of rotation of the upper part of said disc, said housing having a chip outlet through which the chips are discharged, a plurality of chipping blades secured to said disc at circumferentially spaced locations, said blades including cutting edges projecting from said face of said disc to slice across the end of a slab supported in a horizontal position on said base, said blades extending toward the periphery of said disc in a nonradial direction with the outer end of said edges being angularly displaced from the inner end thereof in the direction of rotaion of said disc so that said edges lead the radial line drawn from the center of rotation of said disc through the inner end of said cutting edges whereby the slab is securely held in a substantially horizontal position on said base as said blade edges slice across the end of the slab moving downwardly and outwardly from substantially the beginning to the end of the engagement of the slab by said edges.

In particular, this invention can be more completely and fully understood by reference to the accompanying drawings illustrating a specific embodiment thereof. In these drawings:

FIGURE 1 is a plan view of an embodiment of the wood chipper of this invention with the feed spout atta-ched.

FIGURE 2 is an elevation view of the wood chipper as shown in FIGURE 1.

FIGURE 3 is an auxiliary view taken along the line 3-3 in FIGURE 1.

FIGURE 4 is a detail view of the rotatable disc of the wood chipper assembly showing the arrangement of the chipping blades thereon, and showing the outline of the feed spout in phantom lines.

Referring to the drawings, a cutter disc 1 is rotatably mounted upon shaft 2, which is rigidly held in position by bearing assemblies 3, as best seen in FIGURE 1. The disc may be of any suitable material such as steel or cast iron. Disc 1 is positioned within a removal housing 4 which includes an outlet opening 5, shown here to be generally tangential to the rotating disc, through which the chips produced during the chipping operation are discharged. This outlet opening 5 can be arranged in any position, as needed for the particular chipping operation.

The chipper disc 1 and housing 4 are supported in position by bolts 10 connecting the bearing assemblies 3 to the foundation plate 11. Plate 11 is in turn fixed to a supporting foundation, not shown, by bolts 12. Support member 13 is connected to braces 14 by bolts 15 so that member 13 is held in a vertical position substantially parallel to the face of disc 1.

Feed spout 22 extends through member 13 and terminates at an inlet opening 20 as best seen in FIGURE '1. The inlet opening 29 is positioned above the center of rotation of shaft 2 and laterally displaced from the shaft in the direction of rotation of the upper part of disc 1. The feed spout 22 is removably connected to member 13 by screws 23. The bottom portion of spout 22 defines a flat horizontal base 24 extending horizontally to inlet 20 adjacent the disc 1. A horizontal bed knife may be positioned at the bottom of the inlet 20 with a sharp edge extending along the line 21 as shown in FIGURE 4. The bed knife 21 may be a removable hardened steel plate, not shown, positioned adjacent to the disc 1.

The wood slabs to be chipped are thus fed through spout 22 along flat base 24 toward the bed knife 21, and supported in a horizontal position by the flat base and the bed knife during the chipping operation.

As shown in FIGURE 1, the feed spout is preferably inclined outwardly from the axis of the cutter disc 1 so the slabs are fed to the rotating disc 1 along the same inclination. The inclination of the spout is preferably 45 but can be varied in accordance with requirements of particular installations.

Rotatable disc 1 has a plurality of chipping blades 30 mounted symmetrically at circumferentially spaced locations thereon as shown in FIGURE 4. According to this invention, blades 30 are secured to disc 1 by any suitable blade clamping means, so that the cutting edges 31 exradial direction. The direction of rotation of disc 1 is indicated by the arrow in FIGURE 4.

The outer ends of cutting edges 31, the end closest tothe periphery of the disc, are angularly displaced from. the inner ends thereof in the direction of rotation of the disc, so that the cutting edge of each blade leads a radius R, extending from the center of rotation of the disc through the inner end of the cutting edge of each blade- This blade placement is clearly illustrated in FIGURE.

4 for use on a right-hand chipper, Where the disc 1 rotates clockwise about shaft 2. In contrast, the cutting edges 31 would lead the radius R in the opposite direction when the disc 1 is to be used with a left-hand chipper.. Preferably, wear plates 35 are removably mounted on the face of disc 1 in front of the cutting edges 31 to pro-- long the useful life of the disc. Similarly, chip slots 36 are preferably provided which slots extend axially through disc 1 adjacent to the cutting edge 31 so that the chips produced will be carried through the chip slots to the back of the disc 1 and discharged through outlet 5.

In operation, disc 1 is rotated on shaft 2 by any suit able power source, not shown. The wood slabs or the like to be chipped are fed into feed spout 22 toward the rotating disc 1 and are supported in a horizontal position by the fiat horizontal base 24 and bed knife 21. As the slabs are continuously fed into the chipper, the rotation of disc 1 brings chipping blades 30, and cutting edges 31, into successive contact with the end of the slab to be chipped. During this chipping operation, the cutting edges 31 first contact the slab on the top of its inner end,. near the center of rotation of the disc, and proceed to slice through the slab downwardly and outwardly toward the periphery of the disc. The slab is thus chipped from 'side to side to produce uniform, high quality chips. The

downward and outward movement of the blade relative to the slab during the entire period of engagement of the blade and the slab holds the latter firmly against the flat base and the outer wall of the feed spout.

By fixing the blades 30 to the rotating disc according to this invention, the downward force of the cutting edges 31 on the wood slab being chipped is greatly increased in comparison to that produced by previously known wood chippers. This increased downward force of the cutting edges 31 stabilizes the chipping operation by securely holding the slabs being chipped in a flat horizontal position upon the flat base 24 of the feed spout 22. This invention, therefore, greatly reduces the vibration and tipping of the wood slabs in the feed spout and improves the efficiency of the chipper and the quality 'of the resulting chips.

It is desired to obtain a downward force on the slabs being chipped, while still insuring that the slabs will be sliced from edge to edge. Where the knife moves directly downwardly, it slices across the grain. This breaks the chips too finely and tends to shatter the slab. Thus, it is preferred to arrange the blades so that each blade successively moves into a positionsubstantially parallel to the bed knife 21 only after the blade has passed the bed knife and completely out through the slab. Thus, as seen in FIGURE 4, the cutting edge 31' of blade 30 is substantially parallel to the bottom of the inlet 20* or the horizontal bed knife 21 only after the blade has been rotated to a position below the inlet bottom.

The angle in which the blade moves across the slab may be varied by changing the inclination of the blade leading edge relative to a radial line from the axis of the disc. Edge to edge movement is emphasized by diminishingthe inclination. Downward movementis emphasized by increasing the inclination. An inclination is selected which insures that the movement is edge to edge across the entire slab and downward from substantially the knife may be moving slightly upwardly rather than downwardly when it first contacts the edge of the slab. This is not serious so long as the major portions of the knife stroke across the slab is downward and at least one knife is moving downwardly through the slab when the succeeding knife first contacts .the slab edge. Onnarrower slabs the action would be entirely downward over the entire stroke of the knife.

While a single embodiment of this invention has been described herein, various modifications may be made without departing from the scope of this invention, which is defined solely by the appended claims.

What is claimed is:

1. A chipper for chipping wood slabs and the like comprising a housing, a vertical cutting disc 'rotatably mounted on a horizontal shaft in said housing, a feed spout extending into the housing to receive a slab to be chipped, said feed spout including a flat horizontal base to support the slab during the chipping operation, said base having its inner end adjacent the outer face of'said disc, said inner end being fixed above the center of'rotation of said shaft and laterally displaced from said shaft in the direction of rotation of the upper part of said disc, said housing having a chip outlet throughwhich the chips are discharged, a plurality of chipping blades secured to said disc at circumferentially spaced locations, said blades including cutting edges projecting from said face of said disc to slice across the 'end ofa slab supported in a horizontal position on said "base, said blades extending toward the periphery of said disc in a nonradial direction with the outer end of 'saidedges being angularly displaced from the inner end thereof in the direction of rotation of said disc so that 'said'edges lead the radial line drawn from the center of rotation of said disc through the inner end of said cutting edges, whereby the slab is securely held in a substantially horizontal position on said base as said blade edges slice across the end of the slab moving downwardlyand out-v wardly from substantially the beginning 'to the v,end of the engagement of the slab by said edges.

2. A chipper according to claim v1 wherein said cutting edge of each of said blades is substantially parallel tosaid 'base only after said edges pass said base during their cutting movement.

3. A chipper according to claim 2 wherein said feed spout is inclined outwardly from the axis of said-"disc so that the slab is inclined outwardly as it is fed toward said disc.

4. A chipper according to claim 1 wherein said disc includes chip slots extending axially therethrough parallel to said cutting edges of said blades and in front of said edges in the direction of rotation of said disc so that the chips produced by said blades discharge at'the back-of said disc.

5. A chipper according to claim 4 wherein wear plates are removably secured to said'face of said disc adjacent to said chip slots and in front of said slots in the direction of rotation of said disc.

References Cited by the Examiner UNITED STATES PATENTS 2,712,904 7/1955 Durkee 144-4219 X 3,030,987 4/1962 Jackson et a1. 144-176 X FOREIGN PATENTS 647,374 8/1962 Canada.

WILLIAM W. DYER, JR., Primary Examiner.

W. D. BRAY, Assistant Examiner. 

1. A CHIPPER FOR CHIPPING WOOD SLABS AND THE LIKE COMPRISING A HOUSING, A VERTICAL CUTTING DISC ROTATABLY MOUNTED ON A HORIZONTAL SHAFT IN SAID HOUSING, A FEED SPOUT EXTENDING INTO THE HOUSING TO RECEIVE A SLAB TO BE CHIPPED, SAID FEED SPOUT INCLUDING A FLAT HORIZONTAL BASE TO SUPPORT THE SLAB DURING THE CHIPPING OPERATION, SAID BASE HAVING ITS INNER END ADJACENT THE OUTER FACE OF SAID DISC, SAID INNER END BEING FIXED ABOVE THE CENTER OF ROTATION OF SAID SHAFT AND LATERALLY DISPLACED FROM SAID SHAFT IN THE DIRECTION OF ROTATION OF THE UPPER PART OF SAID DISC, SAID HOUSING HAVING A CHIP OUTLET THROUGH WHICH THE CHIPS ARE DISCHARGED, A PLURALITY OF CHIPPING BLADES SECURED TO SAID DISC AT CIRCUMFERENTIALLY SPACED LOCATIONS, SAID BLADES INCLUDING CUTTING EDGES PROJECTING FROM SAID FACE OF SAID DISC TO SLICE ACROSS THE END OF A SLAB SUPPORTED IN A HORIZONTAL POSITION ON SAID BASE, SAID BLADES EXTENDING TOWARD THE PERIPHERY OF SAID DISC IN A NONRADIAL DIRECTION WITH THE OUTER END OF SAID EDGES BEING ANGULARLY DISPLACED FROM THE INNER END THEREOF IN THE DIRECTION OF ROTATION OF SAID DISC SO THAT SAID EDGES LEAD THE RADIAL LINE DRAWN FROM THE CENTER OF ROTATION OF SAID DISC THROUGH THE INNER END OF SAID CUTTING EDGES, WHEREBY THE SLAB IS SECURELY HELD IN A SUBSTANTIALLY HORIZONTAL POSITION ON SAID BASE AS SAID BLADE EDGES SLICE ACROSS THE END OF THE SLAB MOVING DOWNWARDLY AND OUTWARDLY FROM SUBSTANTIALLY THE BEGINNING TO THE END OF THE ENGAGEMENT OF THE SLAB BY SAID EDGES. 